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5 Sheets-Sheet 1. 4 J. STEHLI. MET-AL SCREW MACHINE.

(No Model.)

WITNESSES 24-05% fiww (No Model.) 5 Sheets-Sheet 2.

. J. STEHLI.

METAL SCREW MACHINE.

No. 351,291. Patented Oct. 19, 1886.

WITNESSES l/Vl/E/VTUH By 4 Afforne J N. PETiflS Piwmwm n mr, Washingion.n. c.

(No ModeL) 5 Sheets- Sheet 3. J. STEHLI. METAL SCREW MACHINE.

No. 351,291. Patented Oct. 19, 1886.

INVENTOR ATTOR EYS wgssstzs: W W2 N. FETER5. PhololilhognphlnWashington. D. C

5 Sheets-Sheet 4.

J. STBHLI. METAL SCREW MACHINE.

(No Model.)-

No. 351,291; Patented Oct. 19, 1886.

WITNESSES:

ATT RIVEYS N. PETERS. PhovrLhhugnphar. Washington. a. c.

no Model.) '5 Sheets-Sheet 5.

J. STBHLI METAL SCREW MAGHINE. No. 351,291. Patented Oct. 19,1886.

Jay 0.

WIT/M8858: IIVI/EIVTOI? Mia W01 8) rrrcn.

JAKOB STEHLI, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE HART- FORDMACHINE SCREWV COMPANY, OF SAME PLACE.

M ETAL=SCREW MACHINE.

SPECIFICATION forming part of Letters Patent No. 351,291, dated October19, 1886.

(No model.)

To all whom it may concern:

Be it known that I, JAKOB STEHLI, of Hartford, in the county of Hartfordand State of Connecticut, have invented certain new and usefulImprovements in Metal Screw Machines, of which the following is aspecification.

This invention relates to certain improvements in the machine for makingmetal screws for which Letters Patent of the United States have beengranted to me on July 22, 1884, No. 302,525, the improvements beingdesigned with aview to simplify the construction of the ma chine, renderthe operation of the same more accurate and effective, and increaseconsiderably the productive capacity of the machine.

Theinvention consists of a metalserew machine in which the operatingelementst wit., the reciprocating carriage, the revolving mandrel withits quill and chuck, the wireholding jaws, the reducing-tool, thethreadingdie, and the cutting-offtoolsare operated by a series of camson a main shaft that is located longitudinally below the table of themachine, and by intermediate lransmitting-- levers, by which dispositionof the shaft the transmitting mechanisms are considerably simplified andrendered more accurate.

The invention consists, first, of an advance cutter that workssimultaneously with the cutting-off tool, wherebythe cutting off of thefinished screw is accelerated and a better finish given to the head ofthe same. The invention consists, further, of an automatic stopmotion bywhich the main shaft is thrown out of gear with the power-transmittingshaft in case the wire inthe mandrel has been worked up, so that thecutting-tools are not injured by the short piece of wire in the machine.

The invention consists, further, of certain details of construction andcombination of parts,- which will be more fully described hereinafter,and finally be pointed out in the claims.

In the accompanying drawings, Figure 1 represents a side elevation of myimproved screw-machine, showing the mandrel and motion-transmittingworm-gear in vertical longitudinal section. Fig. 2 is a plan of the samewith some of the parts shown in section. Fig. Fig. 4.

3 is an end elevation of the machine.

gitudinal bedplate, A and a horizontal table, 6

A, above which the different working parts are arranged. Below the tableis supported in bearings c a of the standards A A the longitudinal mainshaft B, which receives slow rotary motion by a worm.-gear-wheeltransmission from a transverse shaft, B, at one end of the machine, saidshaft carrying a conepulley, B, that may be thrown by a clutch mechanismand a stop-motion, to be hereinafter described, in or out of gear withthe transverse shaft B, so as to automatically interrupt thetransmission of power to the main shaft, and interrupt thereby theworking of the machine.

On thelongitudinal shaft B are arranged eight 8 actuating-cams ofdifferent sizes and shapes, which transmit by means of intermediatetransmitting lever mechanisms the required motion to the differentworking parts of the machine. in Fig. 1, and in detail in Figs. 7 to 14.The cams are designated by the letters a, ((1 ,60 a, a a, a and (1'according to their succession on the main shaft B, and so shaped thatfor each rotation of the main shaft the working parts of the machineproduce a complete metal screw. The dilferent working parts are soadjusted that any size of screw within certain ranges may be made,smaller sizes of screws These cams are shown in side view 8 5 requiringa smaller machine, while larger sizes 9 5 of screws require a largermachine.

On the table A is arranged a fixed dovetailed guide-plate, A whichserves to guide the correspondingly-recesscd base-plate of areciprocating carriage, D. The carriage D supports in vertical standardsD a mandrel, D The carriage D, and the mandrel D, sup

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ported thereon, are moved forward by the cam a, and a fulcrumed lever,b, which is provided at the lower end with an anti-friction roller thatmoves along the face of the cam a. The cam a is shown in side view inFig. 1, in end view in Fig. 7, and in circumferential development inFig. 7. Its face or circumference is provided with inclined parts anddepressions, whereby the motion of the carriage is controlled for thepurposes to be hereinafter described. The fulcrum of the lever 1) turnsin bearings of the table A, which bearings project laterally beyond thetable, so as to give the required steadiness of support'to the same.projecting nose, I), the threaded shank of which is screwed into adovetailed slide-piece, If, that is guided in correspondinglydovetailedways of an upright pillar, I), supported rigidly at one side of thecarriage D, as shown in Figs. 1, 2, and 5. The slide-piece b is adjustedin the pillar b by a screw, 1), which turns in a sleeve, b, at the otherend, and engages a nut on the slide-piece, as shown in Fig.

2, so as to readily raise or lower the same, ac-

cording to the length of forward motion that has to be given to thecarriage, which motion corresponds to the length of screws to be made.At the upper end of the lever b is arranged a set-screw, 12 which servesto move the carriage forward to the threading-die, especially whenscrews of small size are to be made, so that the length of thread isregulated and the threading-die prevented from touching the re: ducingand cuttingoft tools and injuring the same. The set-screw b is properlyadjusted in all cases, and has the advantage of securing the exactdegree of motion of the carriage D. The forward motion of thecarriagc'takes place intermittently, according to the configuration ofthe face of the cam a, acting on the lever b, the carriage being'firstmoved forward, then it dwells and moves slightly backward, when thelever arrives at the depression in the face of the cam, which recedingmotion takes place at the moment when the reducing-tool has accomplishedits work, then forward again for forming the head, then backward, afterwhich the carriage is held in position for cutting off the screw, itbeing then quickly moved back to its starting position. The returnmotion of the carriage is accomplished by a strong spiral spring orsprings, b, that are attached. to lugs b projecting through slots of thebase-plate of the carriage and table, and to fixed lugs b of the table,as shown in Fig. 1.

The mandrel D is provided with two loose pulleys, p p, and anintermediate fast pulley,

p, by which, in connection with a belt, 19, and

cross-belt 1 a forked belt-shifting lever, p, and the cam a, rotarymotion is .imparted to the mandrel D" in one 'or the opposite direction.The lever 'p is operated by the cam a, which is 'fulcrumed to the lugs bbelow the table A, and provided at its lower end with an anti-frictionroller that bears on the cir- The lever b engages near its fulcrum a ofthe mandrel take place as soon as the threading-die has cut the threadon the reduced shank of the screw, so as to unscrew the same from thethreading-die. The return motion of the belt-shifting lever p is causedby the tension of the belts p p.

The base-plate of the carriage D is provided at one side and near itsfront end with a downwardly-extending piece, 8, that carries ahorizontal adjustable stop, 8. The fulcru med stoplever s is operated bythe cam a (shown in Figs. 1, 9, and 9,) and by a spiral spring, 8, bywhich the anti-friction roller at the lower end of the lever s is heldin contact with the circumferential face of the cam a".

The movement of the carriage D and the operation of the tools forcutting off the screws is timed in such a manner that during the forwardslidingof the carriage, and immediately before the cutting-off toolsbegin to perform their work the cam a will operate the stoplever s andthrow the upper arm of the same downwardly into the path of the stop 8,so that the latter will strike against the upper arm of the lever s andstop the carriage until the cutting-off tools have entirely accomplishedtheir work. The stop-lever s will then be moved up by the cam a and theaction of the spring 8 out of the way of the stop 3 as shown in Fig. 1,so as to permit the carriage to move back to its starting position.

Within the mandrel D is supported a quill or sleeve, D, which isprovided at the front end with a conically-tapering chuck, D, that isformed of spring-jaws which are fitted into the correspondingly-flaringend of the mandrel D. The chuck D is clamped thereby to the wire fromwhich the screws are made, which wire is passed centrally through thequill D and held firmly in position by the IIO jaws of the chuck D, aslong as the chuck is drawn into the flaring end of the mandrel by theaction of two levers, d, on a shoulder, d", at the rear end of thequill- The levers df are fulcrumed to a sleeve, D of the mandrel D whichsleeve is provided with slots for the levers d. The levers d extendthrough the slots of the sleeve to the interior of'the mandrel, andengage by projections or noses d the shoulder d at the end of the quillD. The outer ends of the levers d are engaged by the curved hub of asleeve, (1, which slides on the mandrel D and has parallel collars dthat are engaged by anti-friction rollers d at the upper forked end of alever, (1 The lever d is fulcrumed to the base-plate of the carriage D,and

provided at its lower curved end with an anti- Lil the curved lever 11the sleeve (1* is quickly pushed backward, whereby the levers d are'l'QlCZlSQCTfIOIlItllO shoulder d of the quill, so that the chuck at thefront end of the same is free to release thewire and slide along thesame in following the backward motion of the carriage D without carryingitalong. As soon as the lever d has passed the cam groove of the cam (r,the latter moves the sleeve (1" forward, so that its huh acts upon thelevers d and spreads them apart, whereby the projections at theinnerends of the levers d engage the shoulder (F at the end of the quill Dand move the latter backward in the mandrel D". This motion ofthe quilldraws the chuck D* tightly into the flaring end of the mandrel D", sothat the same rigidly clamps the wire. The cam 0?, together with itsnosepiece (Z forming the cam-groove, is made of such a width as toprovide for the extent of reciproeating motion of the carriage D; or, inother words, for the length of screw to be made so that the lever d canmove with the carriage and operate the quill and chuck in the mannerdescribed.

Eis the reducingtool, which is accurately adjusted by set screws in alaterally-movable slide-plate E, that moves by dovetailed ways 6 on atransverse guidepicce, E of a standard, A, of the supporting-t'rame. Theslideplate E is longitudinally adjustable on the dovetailed ways 0 by ascrew, 6. (Shown in Figs. 1, 2, and 3.) The slide-plate E is providedwith a vertically adjustable plate, E", which carries an adjustablescrew, E", below the reducing-tool E, as shown in Fig. 3, so that thescrew E can be adjusted higher or lower for permitting the reducing-toolto be moved back to a greater or less extent, according to the size ofthe head tobet'ormed 011 the screw. The slide-plate E is moved byastrong spiral spring, E in a lateral direction until stopped by anadjustable set screw, E, the spring pressing the rcducingtool E againstthe wire and reducing it to the required thickness of shank inconjunction with the quick rotary motion imparted thereto by themandrel. The cam a (shown in Figs. 1, 3, and 13) operates a fulcrumedlever, c which acts by its upper end on the screw E" so as to move thereducing-tool E against the tension of the spiral spring E sidewise andout of the way of the head of the metal screw when the tool E hasaccomplished its work.

\Vhen the reducing-tool E has formed the shank of the metal screw, thethreadingdie F is thrown into operation so as to cut the thread on theshank. The threading-die Fis attached to one end of a longitudinalsliderod, F, that is guided insl'eeves F ofa standard, F. The oppositeend of the slide-rod F is acted upon by an elbow-lever, f, that isfulcrumed to the end standard, A, and operated by a cam, a (Shown inFigs. 1 and 14.)

As soon as the threading of the shank is completed, the same is releasedfrom the threading-die by the reverse motion imparted to the mandrel andwire by the shifting of the belts, upon which the lever f and thethreading-die F are returned to their former positions. The carriage Dis now moved back by the cam a as far as required for the thickness ofthe head to be formed on the screw, and then stopped and held in astationary position by means of the stop-lever S and stop S, actuated bythe cam a", as before described. The screw is now ready to be cut offfrom the wire, which is accomplished by an advance cutter, G, and acutting-off tool, H, which cutters act nearly simultaneously on thewire.

The use of an advance cutter and a cuttingoff tool has the advantagethat not only about one-half of the time heretofore required for cuttingoff the screw is saved, but also the cutter-marks which are produced bythe single cutter at the center of the heads are entirely done away withand a perfectly-smooth head obtained.

The advance cutter G is operated by the cam a, a double slide-rod, g,guided in a slot, of a-standard, A a t'ulcrumed and slotted intermediatelever, 1 a connecting-link, g, which is pivoted to the lever and the advance cutter G, that is guided in ways 1/ of an upright standard, A Onthe slotted end of the lever g the slide-rod 9 can be adjusted, so thatthe stroke of the. advance cutter can be regulated according to the sizeof the heads of the screws. The guideways g of the advance cutter G areadjusted by set screws y and a swivel-screw, g, which enables theadvance cutter to be set readily to the center of the wire.

The actuating mechanism of the advance cutter G and its cam a is shownclearly in Figs. 1 and 4. The cutting-off too] His located opposite tothe reducing tool E on a slide plate, H, that is guided and adjusted inthe same manner as the reducing-tool E. The out ting-oft tool H is alsooperated by the cam. (LT and t'ulcrumcd lever c, which latter moves thereducing cutter sidewise and applies then the cutting-off tool, so thatit follows in the path of the advance cutter G and cuts oi't' the furishcd screw in a neat and smooth manner. As soon as the cuttingot'f toolH has accomplished its work,the chuck D releases the wire by the motionof the cam a and the forked lever d on the quill D", whilesimultaneously the end of the wire is rigidly clamped in position by amovable jaw, 1, against a fixed jaw, I, which jaws are arranged on thatside 01' the standard A facing the mandrel. The movable jaw lis operatedby a tulcrumed lever, 11, and the cam (6 (Shown in Figs. 1 and 4.) Theupright standard A also supports a fixed guide-sleeve, K, for the wire,in front of which the reducing, advance, and 'cuttingoff tools arearranged, as shown clearly in Fig. 2, while the clamping-jaws I l arearranged at the other side of the standard A The sleeve K serves toguide the wire steadily to the reducing-tool and threading-die and toexpose it to the action of the advance cutter and cutting-off tool.

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4 y l v 351,291

As soon as the carriage and mandrel are returned to their normalposition, the wire-holding jaws release the wire, while the chuck at thefront end of the mandrel clamps it again by the action of the cam a andlever (2 By the return-motion of the carriage the quill is moved alongthe wire for a length required for the next screw. The carriage is' thenmoved forward again by the action of the cam a, so as to complete thenext screw, and so on.

In case the wire has been fed forward through the quill, until a smallpiece only remains, which would be held by the jaws I I, and be entirelyreleased from the quill by the receding motion of the carriage, the nextforward motion of the carriage wouldcause the chuck at the end of thequill to push the small piece of wire forward, which would then beliable to injure thecutting-off tools, as it would not be guidedcentrally by the quill.

To prevent injury to the cutting-tools an automatic stop -motion isprovided, which, whenever the wire has been spent, throws the transverseshaft B out of gear with the conepulley B The stopmotion consists ofadrop- .pin, L, which passes through a slot of the mandrel anddiametrieal slots of the quill near the chuck of the same, when theendof the wire has passed said slots. WVhile the wire is still in thequill the drop-pin L rests on the wire, as shown in Figs. 1 and 6. Thedrop-pin Lis supported bythe forked end of a curved lever, L, which isfulcrumed to the mandrel. D and acted upon at its other end by a spring,as shown in. Fig. 6. At the moment when the drop-pin L is dropped intothe slots of the quillthat' is, at the moment when the end of the wirehas passed the slots of the quillthe spring-actuated end of the lever Lis forced.

in outward direction, so as to engage an arm,

L of a longitudinal rod, L", which is guided in bearings ll of thebase-plate ofthe carriage D, as shown in Figs. 2 and 6. The rod Lextends over the transverse shaft B, and is provided at that end with-asecond arm, Z, that is thrown into line with a set'screw, Z, of anoscillating arm, L when the oscillating arm L is struck by the end ofthe lever Z. The oscillating arm L is hinged to the end standard, A, ofthe supporting-frame A, and retained in upright position by the pressureof a crosspin, Z, of a transverse rod, L, that is guided in lugs Z" ofthe frame A, and provided with a collar, Z. The rod L is acted upon by astrong spiral spring, Z, which is interposed between the collar Z" andone of the lugs Z, as shown in Fig.2. Atthe momentwhen the arm L pushesthe oscillating arm L back, so that the latter clears the cross-pin Z",the spiral spring Z forces the transverse rod L sidewise. A lug, l, at

the end of the rod Z, engages a collar of the eonepulley B so as tomovethe latter sidewise on the shaft B, and throw it by a suitable clutchmechanism out of gear with the same. The machine is then instantlystopped, as no motion is transmitted to the main shaft. The attendanthas to insert anew wire into the quill, upon which the work of themachine is resumed.

The stop-motion forms an essential feature of my improved machine, asthereby the ma chine .is protected against injury by careless andinattentive workmen.

The operation of the machine is as follows: The carriage D is movedforward by the action of the cam a and lever 12, as hereinbeforedescribed, and thereby the wire fed forward. Simultaneously the quill Dtightly clamps the wire by the action of the cam a and lever (1 so thatboth rotate with the mandrel D By the forward motion of the wire thesame is exposed to the action of the reducing-tool E,

operated by the cam a and the shank formed thereby exposed to the actionof the threadingdie F, operated by the cam a As soon as the thread hasbeen cut on the reduced shank, the motion of the mandrel is reversed, sothat the shank is unscrewed from" the threading-die, which then dropsback. The carriage and its wire are next moved backward by the action ofthe cam a for the distance of the head of the screw, and lockedstationary in position by the stop 8 and stop-levers, operated by thecam a In this position the advance cutter G and the cutting-off tool Hoperate upon the threaded wire by means of the cams a and a so as to cutoff the screw without nick or blemish on the head. The clamping-jaws I Iare then applied to the wire by the action of the cam (1?, said jawsholding the wire rigidly in position. The stop-lever will release thecarriage D, so that the same can be moved back. Simultaneously the quillwill release the wire by the action of the cam a and the lever d on thelevers (1, so that the quill can ing small metal screws of all kindsused in the manufacture of watches. It can also be used for makingpinions and balance-shafts,in which case the threading mechanism isdispensed with, while the reducing and cutting tools perform the samefunctions; also, by substituting a suitable drilling-tool in place ofthe threading-die, hollow shafts or collars can be made on the machine.

Having thus described inyinvention, I claim as new and desire to secureby Letters Patent 1. The combination of a-longitudinally-reciprocatingcarriage, a rotary mandrel'supported by said carriage, a quill withinsaid mandrel adapted to clamp the wire, and the reducing,'threading,advance-cutting, and cutting-off mechanisms, substantially as set forth.

2. Thecombination of a carriage, means for reciprocating the same, arotary mandrel supported by said carriage, a quill within said mandrel,mechanism for reciprocating said quill independently of the mandrel, areducing-tool, a threading-die, an advance cutter, a cutting-off tool,and mechanism for actuating said tools, substantially as set forth.

3. The combination of a longitudinally-reciprocating carriage, a rotarymandrel supported by the same, an independent] y-reciprocatin g quillwithin said mandrel, mechanism for rotating and reversing the mandrel,and the reducing, threading, advancecutting, and cutting-off mechanisms,substantially as set forth.

4. The combination of a longitudinally-reciprocating carriage, a rotaryhollow mandrel supported by said carriage,a wire-gnidi ng quill withinsaid mandrel adapted to reciprocate in said mandrel and independentlytherefrom, mechanisms for turning down, threading, advance-cutting, andcutting off the screw, jaws for clamping the wire after the screw hasbeen cut off, and a longitudinal cam-shaft having cams for actuatingsaid. mechanisms, substantially as set forth.

The combination of the main shaft B, cam a,fnlcru1ned lever I), havingsetscrew I), carriage D, having a projecting nose,b, and mechanism forvertically adjusting thesame,whereby the extent of motion of thecarriage is regulated, substantially as set forth.

6. The combination of the rotary main shaft B, having cam a and nose (Zfulcrumed lever al having a forked upper end, a rotary mandrel, D asliding sleeve, (1, having curved hub and collar 11", an interior quill,D, having a chuck, D", at one end and a shoulder, (1 at the oppositeend, and levers d, fulcrumed to a sleeve of the mandrel, and havinginterior noses, d, engaging the shoulder d, so as to move the quillindependently of the mandrel, substantially as set forth.

7. The combination of the longitudinalmain shaft B,having cam a, afulcrumed and springactuated stop -lever, s, and a reciprocatingcarriage, D, having an adjustable stop device, s", at one side thereof,substantially as set forth.

8. The combination ofthe longitudinal main shaft B, a cam, a, with thelongitudinally reciprocating carriage D, a mandrel, D supported by thecarriage, a fast pulley, p, and loose pulleys p on said mandrel, afulcrumed 1everpflhaving belt-shifting devices at the upper end, and abelt and cross-belt, p 1), engaged by said beltshifting device, so as toimpart a rotary motion to the mandrel and reverse the same at the propermoment, substantially as set forth.

9. The combination of the main shaft B, having a cam, a, a fulcrumedlever, i, a movable wire'clamping jaw, I, at the upper end of the leveri, and a fixed jaw, I, supported on an upright standard, A substantiallyas set forth.

10. The combination ofthelongitudinal main shaft B, cam a fulcrumedlever 0 an. upright standard. A, laterally -reciprocating slide-plates EH, spring E reducing-tool E, and cutting-off tool H, supported by saidslide plates, and setscrews E and E, substantially as set forth.

11. The combination of the main shaft B, adjustable slider-0d g, uprightstandard A having slots 9 and ways 9, fulcrumed and slotted lever g,connectinglink g", and a laterally-adj nstable advance cutter, G, guidedin the ways 9, substantially as set forth.

12. The combination of a longitudinallyreciprocating carriage having amandrel supported on said carriage, an independentlyrcciprocating quillwithin said mandrel, mech anisms for reducing, threading, and cuttingoff the screw, and a stop-moti0n connecting the mandrel and quill withthe clutch mechanism on the driving-shaft, so as to stop the motion ofthe machine whenever the end of the wire leaves the quill, substantiallyas set forth.

13. The combination of a reciprocating earriage, D, a mandrel, D,supported by said can riage, an interior independently-reciprocatingquill, D, a drop-pin, L, passing through slots of the mandrel and quill,a spring-actuated lever, L, fulcrumed to the mandrel and engaging thedrop-pin L, a longitudinal rod, L having arms L and Z, a hinged arm, L,

having a set-screw, Z, and a transverselyguided and spring-actuatedshaft, L having cross-pin Z and lug Z the latter engaging the clutch ofthe driving-shaft, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed myname in presence of two subscribing witnesses.

JAKOB STEHLI.

\Vitnesses:

A. OATMAN, G120. M. Bonn.

